Blockchain

Seminar Topic on Blockchain

 A blockchain originally block chain is a growing list of records, called blocks, which are linked using cryptography.Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data (generally represented as a merkle tree root hash).

A Brief History of Blockchain

To start, let’s talk about the history of the blockchain. Before it was ever used in cryptocurrency, it had humble beginnings as a concept in computer science — particularly, in the domains of cryptography and data structures.

The very primitive form of the blockchain was the hash tree, also known as a Merkle tree. This data structure was patented by Ralph Merkle in 1979, and functioned by verifying and handling data between computer systems. In a peer-to-peer network of computers, validating data was important to make sure nothing was altered or changed during transfer. It also helped to ensure that false data was not sent. In essence, it is used to maintain and prove the integrity of data being shared

In 1991, the Merkle tree was used to create a “secured chain of blocks” — a series of data records, each connected to the one before it. The newest record in this chain would contain the history of the entire chain. And thus, the blockchain was created.

In 2008, Satoshi Nakamato conceptualized the distributed blockchain. It would contain a secure history of data exchanges, utilize a peer-to-peer network to time stamp and verify each exchange, and could be managed autonomously without a central authority. This became the backbone of Bitcoin. And thus, the blockchain we know today was born, as well as the world of cryptocurrencies.

How does the blockchain work?

Any data put into the blockchain must be verified. Transactions are grouped together in blocks, hence the name blockchain, then verified by the computers (nodes) in the network. When a computer joins the network as a node, they receive a copy of the blockchain which acts as proof of all the transactions that have been performed.

This means that all data stored on the network is transparent; it is public by default. This also means that all the data in the blockchain network cannot be corrupted or deleted.

However, this doesn’t mean you can see who is doing the transaction. For instance, with bitcoin, the public can see that someone is sending an amount to someone else but there is no information linking the transaction to anyone. This is because the public keys linking the transaction are kept anonymous.

As well, it is un-hackable because it doesn’t have a centralised system. Instead, it is hosted by millions of nodes around the world, instead of being in one central place.

Source

https://en.wikipedia.org/wiki/Blockchain
https://www.investinblockchain.com/what-is-blockchain-technology/
https://www.standard.co.uk/tech/what-is-blockchain-explainer-uses-importance-a3779746.html